236 
PACIFIC SCIENCE, Vol. II, October, 1948 
surface of the sediment were obtained. On the 
other hand, distinct reflexes from depths vary¬ 
ing between 60 and 180 meters were repeatedly 
obtained. In one case where the corer had been 
stopped by a superficial layer of lava, distinct 
reflexes from depths similar to those mentioned 
in the sentence above were obtained, which 
indicates that the superficial layer of lava is 
evidently not impenetrable to the acoustic waves 
recorded by our hydrophones. 
After a pause of 10 days in Papeete the 
"Albatross” set out on November 2 on a 
northerly course for Hawaii. Oceanographic 
series across the Equatorial Current System 
were made here also, with results very similar 
to those made previously. While under way 
we had occasion to repeat several of the stations 
made over 70 years earlier by the famous 
"Challenger” Expedition, with results corrobo¬ 
rating theirs but with a technique of coring 
which afforded a depth of penetration more 
than 20 times as great. The cores, varying 
from nearly pure radiolarian ooze to nearly pure 
globigerina ooze, displayed highly interesting 
stratificatons, with white calcareous sediment 
alternating with a dark brown or a red clay type. 
It is tempting to ascribe these variations in 
the composition of the sediment to climatic 
fluctuations, acting either directly on the sur¬ 
face temperature of the water and its plankton, 
or possibly causing a displacement of the whole 
current system as the polar ice caps grew and 
varied with inevitable effects on the atmos¬ 
pheric circulation. Here also, especially near 
the Hawaiian Islands, hard bottom interfered 
with coring operations and led to loss of instru¬ 
ments. 
In Honolulu, when we arrived on November 
28, we were most cordially received by munici¬ 
pal authorities, by our colleagues at the Bernice 
P. Bishop Museum and at the University of 
Hawaii, and also by the Scandinavian colony 
represented by the Swe-Nor-Den Society mak¬ 
ing our stay an unmitigated pleasure. We had 
occasion to lay our results before our colleagues 
at a round-table conference at the University 
of Hawaii, and profited greatly from discussions 
there and from most stimulating suggestions 
and advice from Dr. T. A. Jaggar, the greatest 
volcanologist of our time. 
From Honolulu we cruised SW until the 
equator was crossed, changed our course to 
WNW, crossed the equator again, and stopped 
at Kapingamarangi Atoll where submarine light 
measurements were carried out in the sheltered 
waters of the lagoon. At the beginning of this 
segment of our cruise the occurrence of hard 
bottom again made coring operations difficult, 
and the bottom profile presented the same 
rugged and hummocky features as in the eastern 
and central Pacific. Farther west the bottom 
became more even and more amenable to both 
coring and to sediment soundings by depth 
charges. However, adverse winds, to which the 
"Albatross” is rather susceptible because of her 
low-powered auxiliary Diesel engine, made our 
progress slower than we expected. 
In general, the cores taken along our west¬ 
erly course near the equator were of calcareous 
sediment, frequently stratified with brownish- 
gray clay alternating with whitish-gray sedi¬ 
ment. Still farther west a greenish color alter¬ 
nated with gray or brown tones. Our last days 
in the Pacific Ocean were devoted to hydro- 
graphic series and soundings in the southern¬ 
most part of the Mindanao trench. Here a core 
raised from the maximum depth of 7,700 meters 
had a length of only 4 meters, the core sampler 
having been stopped by a layer of coarse sand 
rich in volcanic particles! An attempt to raise 
a core from a still greater depth with an extra 
wire cable attached to the lower end of our 
8,000 meter steel cable failed when the extra 
wire snapped after the corer was on its way 
up. The instrument and its precious content 
were lost. 
Faint but legible echograms were taken at 
cross sections over the trench in latitude 5° 20' 
N. The results prove that the depths given in 
the Snellius charts are several hundred meters 
too great. Attempts to measure the sediment 
thickness in the trench failed because the 
ruggedness of the bottom profile produced 
spurious echoes which obscured any deeper 
